Driving apparatus having an optical sensor and a thermal sensor for thermal and aging compensation of backlight module and driving method of backlight module

A driving method of a backlight module, adapted to a display device, the display device comprising a display panel and the backlight module for providing backlighting illumination to the display panel, the backlight module comprising a plurality of areas and each of the areas having a plurality of light emitting diodes arranged therein, and further the backlight module comprising a lamp board and a metal backplane, the light emitting diodes being arranged on the lamp board and at the front side of the lamp board, the metal backplane being disposed at the rear side of the lamp board, the optical sensor being arranged in contact with the metal backplane rather than the lamp board, and the lamp board being formed with an opening to expose the optical sensor, the driving method comprising:

• only detecting a working temperature of the light emitting diodes of each of the areas, the working temperature being a temperature formed by heat generated from the light emitting diodes;
• providing a plurality of initial thermal compensation tables, obtaining the working temperature and determining working currents of the light emitting diodes of each of the areas corresponding to the working temperature of the light emitting diodes for compensating brightnesses and colors of the areas due to changes of the working temperatures according to the plurality of initial thermal compensation tables respectively;
• detecting brightness and color of the backlight module at the opening by the optical sensor after a calibration function is enabled, so as to obtain difference values of the detected brightness and color with respect to predetermined brightness and color;
• and
• calibrating a content of each of the initial thermal compensation tables corresponding with a current working temperature of the light emitting diodes of each of the areas according to the difference values and storing the calibrated thermal compensation tables as the initial thermal compensation tables, for the achievement of aging compensation of the light emitting diodes of the respective areas.

A driving method of a backlight module, adapted to a display device, the display device comprising a display panel and the backlight module for providing backlighting illumination to the display panel, the backlight module comprising a plurality of light emitting diodes, and further the backlight module comprising a lamp board and a metal backplane, the light emitting diodes being arranged on the lamp board and at the front side of the lamp board, the metal backplane being disposed at the rear side of the lamp board, the optical sensor being mounted to the metal backplane rather than the lamp board, and the lamp board being formed with an opening to expose the optical sensor, the driving method comprising:

• only detecting a working temperature of the light emitting diodes, the working temperature being a temperature formed by heat generated from the light emitting diodes;
• providing an initial thermal compensation table, obtaining the working temperature and determining working currents of the light emitting diodes corresponding to the working temperature of the light emitting diodes for compensating brightness and color of the backlight module due to a change of the working temperature according to the initial thermal compensation table;
• detecting brightness and color of the backlight module at the opening by the optical sensor after a calibration function is enabled, so as to obtain difference values of the detected brightness and color with respect to predetermined brightness and color;
• and
• calibrating a content of the initial thermal compensation table corresponding with a current working temperature of the light emitting diodes according to the difference values and storing the calibrated thermal compensation table as the initial thermal compensation table, as a result of aging compensation of the light emitting diodes.